You should've added a few more pertinent details:
15:57 - The controller clears the aircraft to takeoff advising them landing traffic is on a two-mile final.
16:37 - Pilot who is on short final feels he needs to make comment forty seconds after the departing aircraft was cleared to takeoff.
16:48 - Tower switches departing aircraft to departure eleven seconds after pilot's comment about spacing.
17:15 - Tower gives landing aircraft turn-off instructions during roll-out twenty-two seconds after previous aircraft was switched to departure, forty-three seconds after pilot's comment, and one minute and eighteen seconds after previous aircraft was cleared to takeoff.
Yeah, it was close, but it worked.
What's the pilot doing griping on short final about an aircraft that's already off the ground. There are only two alternatives at that point; either land or go-around. Heck, if the controller wanted to be argumentative his reaction to the pilot's comment could have been to make the go-around decision for him, then I'd bet the pilot would've been whining that he could've made it.
It sounds like the pilot had already anticipated landing behind the first departing aircraft and then was surprised that the controller squeezed another plane out in front of him, and he didn't like it.
It was a useless comment at the moment he said it, and it just comes off as road rage.
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